1. Field of the Invention
This invention pertains to carton unfolding apparatus, and more particularly to apparatus for unfolding open side carton blanks.
2. Description of the Prior Art
Various equipment has been developed to unfold open side carton blanks. The unfolding machinery is often integrated with other apparatus that operates on a continuous basis to open the blanks, load the cartons from one or both sides with the items to be shipped in the cartons, and closing and sealing the loaded cartons.
The folded blanks are usually supplied to the unfolding equipment from a storage hopper in which the blanks are stacked vertically in a pile. Suitable mechanisms are employed to remove the blanks one at a time from the hopper and to deposit them at the first station in the unfolding machinery.
Examples of carton unfolding apparatus are disclosed in U.S. Pat. Nos. 3,060,659; 3,097,463; 3,300,946; 4,067,172; 4,081,945; and 4,358,918. The equipment shown in the foregoing patents are generally quite complicated, and therefore are undesirably expensive and unreliable. Other carton unfolding machinery, such as disclosed in U.S. patent application Ser. No. 602,527 is generally satisfactory for most applications. However specific operating conditions occasionally arise that preclude using prior unfolding devices. In those situations, a need exists for a carton blank unfolding machine that satisfies the specific application in a reliable and economical manner.